1. Field of the Invention
The present invention relates to a window type air conditioner, and more particularly, to a turbo fan housing in an indoor part of a window type air conditioner.
2. Background of the Related Art
FIG. 1 illustrates a longitudinal section of a related art window air conditioner having a sirocco fan applied thereto, inclusive of an indoor part 10 and an outdoor part 20.
The indoor part 10 is provided with an indoor heat exchanger 11 in a front portion thereof, and an indoor fan 12 on an inner side thereof for forced flow of room air into the indoor part 10 through the indoor heat exchanger 11. The indoor fan 12 is surrounded by a fan housing 13 which guides the room air in/out of the indoor part 10. There is an outdoor heat exchanger 21 in a rear portion of the outdoor part 20, and an outdoor fan 23 on an inner side of the outdoor heat exchanger 21 for forced in/out of outdoor air through the outdoor part 20. There is a shroud 24 between the outdoor fan 23 and the outdoor heat exchanger 21, for guiding the outdoor air to the outdoor heat exchanger 21 and therefrom to a rear of the window air conditioner. In the meantime, the indoor fan 12 and the outdoor fan 23 are coupled to both ends of a motor 25 shaft for receiving rotation forces. And, there is a compressor 26 connected to the indoor and outdoor heat exchangers 11 and 21 through a refrigerant tube 27 having a capillary tube(not shown). Since the foregoing window type air conditioner requires a large flow rate, and a high static pressure air, as the indoor fan 12, a sirocco fan(given a reference symbol xe2x80x9c12xe2x80x9d), a kind of centrifugal multi-blade blower, is used as the indoor fan 12 for meeting the above requirements.
FIG. 2 illustrates a section of the fan housing across line Ixe2x80x94I in FIG. 1. Referring to FIG. 2, the sirocco fan 12 is provided with a disk formed main plate 122, a rotating shaft 123 on a center of the main plate 122, a plurality of blades 121 fitted along a circumference of the main plate 122 parallel to the rotating shaft 123, and a rim 124 fixed to free ends of the blades 121. In this instance, the blade 121 is backward curved, with an outlet angle xcex1 greater than 90xc2x0, to enhance an inflow, and a smooth outflow of the room air.
FIG. 3 illustrates a partial perspective view of a fan housing 13 having a related art sirocco fan 12 provided thereto. Referring to FIGS. 1 and 3, the fan housing 13 is provided with a flow guide 131 for accumulating room air discharged from the sirocco fan 12 to form a large quantity of air, and to convert a portion of dynamic pressure of the room air into a static pressure, and a discharge part 132 for discharging the room air through a front face of the window type air conditioner. The flow guide 131 has an inlet plate 131b having a bell mouth 131a formed therein for guiding the room air, a base plate 131c having a rotating shaft 123 of the sirocco fan 12 mounted therein, and a separation wall 131d between the inlet plate 131b and the base plate to surround the sirocco fan 12 in a scroll form. And, there is an opening 131e on one side of the flow guide 131, from which the base plate 131c and the separation wall 131d are extended to form an outlet 132. And, there is a cutoff 133 of a triangular section on an inside of the separation wall 131d connecting a lower portion of the opening 131e in the flow guide 131 and a lower portion of the outlet 132, with a peak higher than a bottom of the outlet 132, for dropping a speed of the room air when the room air flows from the flow guide 131 to the outlet 132, to convert a portion of the dynamic pressure into a static pressure.
When the window type air conditioner is put into operation, the compressor 26 comes into operation so that the refrigerant is involved in compression, condensation, expansion, and evaporation as the refrigerant passes through the compressor 26, the outdoor heat exchanger 21, the capillary tube in the refrigerant tube 27, and the indoor heat exchanger 11. Consequently, the indoor heat exchanger 11 is at a temperature lower than the indoor part, and the outdoor heat exchanger 21 is at a temperature higher than the outdoor part. In the meantime, on the same time with the operation of the compressor 26, the motor 25 also comes into operation to start operation of the sirocco fan 12 and the outdoor fan 23, too. The room air passes, and has a heat exchanged through the indoor heat exchanger 11 as the sirocco fan 12 rotates, and is converted into a low temperature room air. Then, the room air flows in/out of the sirocco fan 12, to flow in a flow passage formed by the sirocco fan 12 and the flow guide 131. The flow passage has a smooth streamlined as the separation wall surrounds the sirocco fan 12 in a scroll form, to facilitate a smooth flow of the room air. However, a section of the flow passage becomes the larger in a direction of the air flow, to reduce a speed of room air as the room air flows along the flow passage, with a rise of the static pressure of the room air as a portion of the dynamic pressure of the room air is converted into a static pressure. Particularly, the static pressure of the room air rises sharply since the speed of the room air drops sharply as the room air passes over the cutoff 133. Eventually, the room air discharged to forward of the window type air conditioner through the outlet 132 has a high static pressure. On the other hand, the outdoor air has a heat exchanged into a high temperature outdoor air as the outdoor air flows through the outdoor heat exchanger 21 via outdoor air inlet holes 22 by the outdoor fan 23, and is discharged out of the outdoor part 20.
However, the window type air conditioner having the related art sirocco fan 12 applied thereto has the following problems.
First, though the sirocco fan has a high pressure and a high flow rate of air, the sirocco fan has a poor fan efficiency, to increase power consumption of the fan motor, resulting in a poor efficiency of the window type air conditioner system.
Second, commercially available turbo fans have a fan efficiency significantly higher than the sirocco fan. However, the turbo fan can not be applied to the indoor fan of the window type air conditioner since the turbo fan has a static pressure and a flow rate poorer than the sirocco fan, when the turbo fan and the sirocco fan are compared in the bulk size basis.
Accordingly, the present invention is directed to a turbo fan housing in a window type air conditioner that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a turbo fan housing in a window type air conditioner, which can provide adequate flow rate and static pressure even if a turbo fan is applied to the window type air conditioner.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the turbo fan housing in a window type air conditioner including a flow guide including an inlet plate having a bell mouth for guiding room air, a base plate opposite to the inlet plate having an indoor fan mounted thereto for drawing the room air, and a separation wall between the inlet plate and the base plate to surround the turbo fan, an outlet formed by extension of the base plate and the separation wall from an opening formed on one side of the flow guide, and a cutoff formed on an inside of the separation wall connecting the outlet and the flow guide, wherein the indoor fan is a turbo fan, and a flow passage in the flow guide is formed to cause sharp flow direction changes, for converting a portion of dynamic pressure of the room air into a static pressure in the flow direction changes.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.